People began to domesticate beer yeasts in the late sixteenth or early seventeenth century, when beer-making in Europe moved from homes to pubs and monasteries.

Credit: Eye of Science/SPL

Kevin Verstrepen at the University of Leuven and Steven Maere at the University of Ghent, both in Belgium, and their colleagues sequenced the genomes of more than 150 strains of Saccharomyces cerevisiae (pictured) used to make bread, beer and other drinks. An evolutionary tree of the strains revealed distinct families of yeast, such as one used to make wine and another sake, as well as two distantly related groups of ale yeast. The beer yeasts showed the strongest signatures of human influence. Beer-making strains carried variations and duplications of genes that break down maltose and maltotriose, the main sugars in beer.

The team used the genomic information to make a hybrid strain that has a high tolerance to alcohol and does not produce 4-vinyl guaiacol, which imbues unpopular clove and smoke flavours.

Cell 166, 1397–1410 (2016)